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Old 17-12-2015, 09:08   #646
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Re: Oyster Problems?

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Expected reveneu, thats all what i want to know... Now you can say if the reputation of the First line, bad or good is unfounded or not...
If I was you I would look with very attention to the Sydney- Hobart that starts in about 12 hours:

Two First 45, a First 50, three First 40, two First 44.7, and First 40.7 are making that race: 9 Beneteau First doing that race on the very bad conditions that are normal on that race, surely one is going to lose the keel.

There is even a First 40.7 that is on its 4th Sydney-Hobart and we all know how they lose keels on normal conditions, much more on the nasty conditions of this race and with the boat being pushed hard:


Or maybe not because I do remember that Beneteau First, since the times of the First 40,7 series, had always several boats making this race, , being the mass production boat with more boats racing and, even if it won the race once and the division many times, to my knowledge it never lost a keel or have problems with it.

Maybe I am wrong, do you remember any case?

Maybe the Australians are crazy. You should explain them that the First 40.7 is a dangerous boat, not suitable for offshore cruising much less to be raced hard on a very nasty offshore race like the Sydney-Hobart.

Funny how the Beneteau First has a good reputation on the Sydney-Hobart
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Old 17-12-2015, 09:12   #647
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Re: Oyster Problems?

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Sure! I'm one of the only boat builders (and by that I mean people who actually get their hands dirty) I know who has an actual degree in boat building. Everyone else I went to school with ended up in design, or in a totally unrelated field. Even my wife!
Interesting comment. I suspect that technology moves faster than education especially as it relates to these new laminates and so on. For example, do they "teach" carbon fiber technology and building in boat building schools?
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Old 17-12-2015, 09:17   #648
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Re: Oyster Problems?

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Interesting comment. I suspect that technology moves faster than education especially as it relates to these new laminates and so on. For example, do they "teach" carbon fiber technology and building in boat building schools?

Sure! They teach it by having me come in and give a talk, with accompanying demonstrations. The whole class has come out to large custom carbon fiber sail boat builds which I was working on, on more than one occasion.
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Old 17-12-2015, 09:25   #649
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Re: Oyster Problems?

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This thread is drifting but interesting. My take away is that the commercial building of yacht hulls is more voodoo engineering then real! Do these engineers, naval architects and yacht builders make it up as they go? Sadly it seems so and this is very troubling... and could lead to loss of life and that could result in criminal and civil actions which could or maybe should sink a company.

Who do you believe? The claims and pretty pictures? What is the training and experience of the marine surveyors who represented the owner's interest ensuring the build quality of some of these expensive one off yachts?

Obviously Oyster had no idea that what they built and sold was not seaworthy. THAT is troubling... as much as their failure to immediately accept responsibility based on the captain's statements. A keel falling off is not acceptable and is a major build/design failure.

Obviously there are many well engineered and built yachts out there. But this thread has revealed too many that aren't. What are these companies thinking?
And yet… the photos and diagrams of Polina Star III drew an, as I believe, unprecedented completely unanimous negative response from all the various quarters and camps of the CF world, a decent few professionals involved. The thickness and arrangement of the structure of that keel had zero supporters here, quite the opposite. And that is something to comment on, for sure. Perhaps there is some arcane world to which we are not privy wherein attaching the entire ballast of a 90 foot yacht with essentially nothing more than 15mm skin layup is acceptable… but none of us on this thread, it seems, are privy to it.

When you say "obviously Oyster" it is hard to tell to whom you are referring… there will be various classes of person involved in the design, construction, fit out, marketing and sale of the vessel… and then there will be the bean counters, and behind them, those with financial interests. It would be absurd to suppose that all knew or cared to appraise themselves of all other parts of the process. Perhaps one of the things which made Matthews' era Oyster so successful was the really extraordinary integration of its workforce, ethos, and vision… I do wonder if that remains the case now, and rather doubt.
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Old 17-12-2015, 09:26   #650
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Re: Oyster Problems?

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Sure! They teach it by having me come in and give a talk, with accompanying demonstrations. The whole class has come out to large custom carbon fiber sail boat builds which I was working on, on more than one occasion.
Hang on a second... where did you learn this technology?
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Old 17-12-2015, 09:34   #651
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Re: Oyster Problems?

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Hang on a second... where did you learn this technology?



The hard way! I started doing factory infusion and vacuum bagging in exotics on a factory floor in '94, fresh out of school. I learned from my fellows on the production floor, as it was the only way to learn this stuff back then. Made the R&D department after one year.
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Old 17-12-2015, 09:43   #652
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Re: Oyster Problems?

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The hard way! I started doing factory infusion and vacuum bagging in exotics on a factory floor in '94, fresh out of school. I learned from my fellows on the production floor, as it was the only way to learn this stuff back then. Made the R&D department after one year.
This is precisely my point. I don't doubt that you are quite a talented and handy builder. I do question and wonder about the sort of engineering studies and testing that new technologies require.

It's my understanding that these sorts of innovations require lots of testing under all manner of conditions. Is this taking place?

How would Oyster know if their "design" was sound? They believed it was. Where did they get this idea from?
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Old 17-12-2015, 09:47   #653
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Re: Oyster Problems?

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This is precisely my point. I don't doubt that you are quite a talented and handy builder. I do question and wonder about the sort of engineering studies and testing that new technologies require.

It's my understanding that these sorts of innovations require lots of testing under all manner of conditions. Is this taking place?

How would Oyster know if their "design" was sound? They believed it was. Where did they get this idea from?
Perhaps you are meaning to suggest that all materials "science" in this direction is much less precise than might be imagined?
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Old 17-12-2015, 09:48   #654
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Re: Oyster Problems?

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Originally Posted by Sandero View Post
This is precisely my point. I don't doubt that you are quite a talented and handy builder. I do question and wonder about the sort of engineering studies and testing that new technologies require.

It's my understanding that these sorts of innovations require lots of testing under all manner of conditions. Is this taking place?

How would Oyster know if their "design" was sound? They believed it was. Where did they get this idea from?



Should be from a chemical engineer. At least that's how it's worked in all the builds I've done in this size range. See Muckle Flugga's signature above for my feelings on that!


Which is of course exactly what is happening here; we begin to suspect the extent of their ignorance!
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Old 17-12-2015, 09:58   #655
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Re: Oyster Problems?

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See Muckle Flugga's signature above for my feelings on that!
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Old 17-12-2015, 10:03   #656
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Re: Oyster Problems?

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This thread is drifting but interesting. My take away is that the commercial building of yacht hulls is more voodoo engineering then real! Do these engineers, naval architects and yacht builders make it up as they go? Sadly it seems so and this is very troubling... and could lead to loss of life and that could result in criminal and civil actions which could or maybe should sink a company.
...
Today most prodution boats are not designed by a NA but by a team of specialist under the supervision of a NA that is the director of the project, pretty much like it is made in what regards designing a car or an airplane.

Big NA cabinets, like the one of Humphreys, has a group of technicians in several departments like composite specialists, structure specialists, Computer fluid dynamic specialists besides designers.

It is to be seen if this was a faulty design or if it was an building error, regarding defective building or building to the specs. We know this was a 825 (a Humphreys design) extended to 90ft. We did not even know if the alteration was made or supervised by Humphreys.

Humphreys is a NA cabinet with huge experience not only in racing boats but also in cruising boats and Humphreys is known to make seaworthy boats. I don't know what happen here but if it is acceptable that on some top racing sailboats experimental techniques and experimental materials can have some small margin of risk, that is not the case regarding cruising boats, being them performance boats or not.

The materials and techniques used here should have already have years of successful testing on race boats.

It is clear what happened but we are still waiting to see why it happened and who is at fault, the designer or the builder.

Regarding your first assertion about yacht design to be more voodoo engineering than real I don't think so and the number of high tech boats that sail without any problem sustain that opinion, but as in anything, Errare humanum est.
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Old 17-12-2015, 10:11   #657
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Re: Oyster Problems?

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Originally Posted by Sandero View Post
This is precisely my point. I don't doubt that you are quite a talented and handy builder. I do question and wonder about the sort of engineering studies and testing that new technologies require.

It's my understanding that these sorts of innovations require lots of testing under all manner of conditions. Is this taking place?

How would Oyster know if their "design" was sound? They believed it was. Where did they get this idea from?
That's a really good and relevant question. A lot of information exists for steel and aluminum alloy materials. Computers can easily simulate performance of these homogeneous materials even to include the welds which interestingly enough are usually stronger than the materials they bond.

But composites are a different material set and the computer tools (finite element analysis) are not much changed. The composite material is less and less homogeneous as you subdivide into very small chunks unlike steel or aluminum which stays pretty much the same until you get to the molecular level. But composites are very much non-homogeneous and also subject to wide variation in the actual fabrication steps (also unlike steel or aluminum).

Historically the yacht industry was so happy to avoid all the problems (and cost) with steel and aluminum that they just massively overbuilt the composite structures to avoid failures. Then oil went to $125/bbl so the cost of the laminating resins and other material skyrocketed. I suspect they tried to use the only computer tools available to analyze the composite materials and these materials are perhaps not well suited to the computer codes that work well in homogeneous materials.

When Boeing went to composites they set up hugely expensive testing programs to validate designs and fabrication techniques whereas in aluminum they could rely on computer simulations and only test at the end. So with the 787 you don't hear much about computer simulations instead you read about massive testing of materials, processes and finished parts to validate the designs.

There is no way the yachting industry can justify design verification by testing the way Boeing did on the 787. Even some financial analysts have questioned Boeing's huge testing costs in the switch to composite materials.

In the case of these keel failures it would be interesting to know if any rigorous failure mode, effects and criticality analysis (FMECA) work was done. before hand. I'm guessing not or if it was the input data could have been faulty. The C step in that process will put the keel attachment right at the top of the criticality list even higher priority than the rig. Thus in that type of design regimen (FMECA) it is difficult to justify, based on effect and criticality, using a safety factor of less than 3 and maybe even 4:1. I'm guessing any reasonable analysis would not support 5mm layups in the keel stub structure to get them to 15mm by multiplying by 3.
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Old 17-12-2015, 10:36   #658
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Re: Oyster Problems?

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That's a really good and relevant question. A lot of information exists for steel and aluminum alloy materials. Computers can easily simulate performance of these homogeneous materials even to include the welds which interestingly enough are usually stronger than the materials they bond.

But composites are a different material set and the computer tools (finite element analysis) are not much changed. The composite material is less and less homogeneous as you subdivide into very small chunks unlike steel or aluminum which stays pretty much the same until you get to the molecular level. But composites are very much non-homogeneous and also subject to wide variation in the actual fabrication steps (also unlike steel or aluminum).

Historically the yacht industry was so happy to avoid all the problems (and cost) with steel and aluminum that they just massively overbuilt the composite structures to avoid failures. Then oil went to $125/bbl so the cost of the laminating resins and other material skyrocketed. I suspect they tried to use the only computer tools available to analyze the composite materials and these materials are perhaps not well suited to the computer codes that work well in homogeneous materials.

When Boeing went to composites they set up hugely expensive testing programs to validate designs and fabrication techniques whereas in aluminum they could rely on computer simulations and only test at the end. So with the 787 you don't hear much about computer simulations instead you read about massive testing of materials, processes and finished parts to validate the designs.

There is no way the yachting industry can justify design verification by testing the way Boeing did on the 787. Even some financial analysts have questioned Boeing's huge testing costs in the switch to composite materials.

In the case of these keel failures it would be interesting to know if any rigorous failure mode, effects and criticality analysis (FMECA) work was done. before hand. I'm guessing not or if it was the input data could have been faulty. The C step in that process will put the keel attachment right at the top of the criticality list even higher priority than the rig. Thus in that type of design regimen (FMECA) it is difficult to justify, based on effect and criticality, using a safety factor of less than 3 and maybe even 4:1. I'm guessing any reasonable analysis would not support 5mm layups in the keel stub structure to get them to 15mm by multiplying by 3.
Thank you and others for the replies to my posts. I understand that composite structures at least in building design require some complex FEA analysis. But the mechanical properties or steel, concrete etc. apparently are much better understood and have been subjected to all manner of destruction testing.

The case of the keel attachment should have been area of special concern because of the large moments a keel can create to the keel to hull connection from heeling. And then add dynamic loading to the equation because in heavy seas the boat is tossed about etc. You have been there.

I am not sure how to err on the side of safety in the connection of keel to hull, but I suspect this is one region to use more tried and true approaches... how much weight can it add? How much additional cost and how much can it degrade the performance? I suspect the answers to these questions will reveal that saving a few pounds was not worth the risk.

The second disturbing thing, if I understood this correctly.... weight had to be added to the bow for trim. How bizarre is that? Why didn't the naval architects properly compute the weight distribution? Maybe I don't understand what was going on... but it strikes me as very weird.

Obviously the average consumer assumes that the builders and architects know what they are doing. And clearly in racing boats it is expected that the designs will push the limits to eek out the every .01 of a knot of speed.

Finally the other thing which strikes me as odd is that this was probably a very expensive project and not likely undertaken with a small profit margin and little room for "give and take" to make the numbers work for the been counters. Surely they could have found pother less critical places to shave some of the cost? I wonder what the profit margins are for such a project.

It's all interesting and clearly the marine building industry is was behind, the aviation, auto and construction industry as far as "testing" and proving are concerned. Maybe.
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Old 17-12-2015, 11:05   #659
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Re: Oyster Problems?

I think the company ethic play a role in the boat industry,, some builders put the ethic and the reputation in top of the list, less profit margin but they are honest and self confident in what they are doing.

Other boat builders, brands ,put the profit margin on top at any cost,,more profit margin, less overall quality.. the clasic is good enough.... kind of a laboratory tests...

Because if Bavaria turn back to bulkheads tabed with FG by hand and the grid glassed in the flanges and a whole diferent way to made things than in the past its because they see the wolf ears, so why? if they market the benefits of plexus glue liners and
bulkheads glued to liner slots in the past? the only logical approach is turn back to clasic and tested methods..
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Old 17-12-2015, 11:26   #660
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Re: Oyster Problems?

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...
The second disturbing thing, if I understood this correctly.... weight had to be added to the bow for trim. How bizarre is that? Why didn't the naval architects properly compute the weight distribution? Maybe I don't understand what was going on... but it strikes me as very weird.
..
On the last post I mentioned that this boat was a Oyster 825 (designed by Humphryes NA cabinet) that was extended, by Oyster to 90ft.

We don't know if Humphryes redesigned the modification but clearly it is not a new design and the ballast at the bow is just a patch to solve a situation of weight distribution created by the increase of length (and new CG), maintaining the boat ballast and keel on the same position as on the 825. I hope Humphryes had nothing to do with that
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